I recently received this question in my email, and because I have no answer, I hope that you might be able to help this reader out with some suggestions. Here's his question:
"I make 3D topographical maps using paper and glue. My next piece is going to have 20 different layers going from a light shade at sea level to a dark shade at the top. The problem that I've come across is that many of my local stores and national suppliers only seem to stock 5 or 6 different shades of a particular colour. I was wondering if you had any knowledge as to where I could find a supplier that stocks 15-20+ different shades of green paper and could potentially ship internationally?"